Connector

ABSTRACT

A connector is provided which has a fluid passage whose volume does not substantially vary with the opening/closing of a valve disc. The connector includes a substantially cylindrical connector main body, a valve disc made of elastic material and disposed at one of the opening ends of the connector main body, and a substantially cylindrical connecting member disposed on the outer periphery of the connector main body on the side of the valve disc and coaxially with the connector main body to be movable in an axial direction of the connector main body.

TECHNICAL FIELD

The present invention relates to a connector for connecting a duct usedin, for example, various medical equipment, fluid infusion containers,and fluid feeding equipment.

BACKGROUND ART

A connector for connecting a duct is provided with a housing and a valvedisc made of elastic material and connected to a connecting port of thishousing, and is structured so as to be positively connected to the ductby this valve disc. The fluid flowing through the duct is fed to theinterior of the connector.

The connector of such type is conventionally known from one disclosedin, for example, JP 9-108361 A.

This connector is provided with the valve disc having a bellows-likesection (bellows section). When a duct is connected to the connector,the bellows section of the valve disc shrinks by means of the duct sothat an end surface of the valve disc is pushed against the duct. Thus,the leakage of liquid from a slit of the valve disc is prevented.

However, in the conventional connector, when the duct is connected tothe connector, the valve disc shrinks so that a flow path volume of theinterior of the valve disc, i.e., the flow path volume of the connectoris decreased in comparison with the case where the valve disc is closed,which causes various problems.

For example, in the case where the connector is connected to a catheterdisposed in a blood vessel and used, the duct is connected to theconnector, and an anticoagulant agent is infused into the catheter fromthe duct through the connector. Thereafter, when the duct is removedaway from the connector, the bellows section of the valve disc isextended so that the flow path volume of the connector is increased. Atthis time, the blood is sucked into the catheter by a negative pressure.

Thus, the blood is coagulated to cause thrombi within the catheter sothat the catheter is clogged and can not be used. For this reason, thecatheter has to be removed. The number of operations is increased toimpose a load to the patient.

DISCLOSURE OF THE INVENTION

An object of the present invention is to provide a connector having afluid passage whose volume does not substantially vary with theopening/closing of a valve disc.

Such an object is attained by the present inventions (1) to (17)described below.

(1) A connector including: a substantially cylindrical connector mainbody having a fluid passage in its interior and opened at both ends; avalve disc disposed at one of opening ends of the connector main bodyand made of elastic material for opening the fluid passage within theconnector main body upon the connection with a duct to be connected tothe connector main body and closing upon the non-connection; and asubstantially cylindrical connecting member disposed on the outerperiphery of the connector main body on a side of the valve disc andcoaxially with the connector main body to be movable in an axialdirection of the connector main body.

(2) The connector according to the above-described item (1), in whichthe valve disc is opened by a pressure from the duct without the ductpassing through the interior of the valve disc.

Normally, the duct has a taper outer peripheral surface that decreasesgradually in a distal end direction. Also, the duct has a lure lock, anda flange is formed at an end section of the connecting member of theconnector. If these are engaged with each other, it is possible to holdthe connection more stably.

(3) The connector according to the above-described item (1) or (2), inwhich the duct is fit to an opening of the connecting member to therebyconnect and hold the duct.

(4) The connector according to any one of the above-described items (1)to (3), further including biasing means for biasing the connectingmember toward the connector main body.

(5) The connector according to the above-described item (4), in whichthe biasing means is composed of a spiral spring, a bellows spring or astepwise spring.

(6) The connector according to any one of the above-described items (1)to (5), further including a position regulating means for regulating aposition of the connecting member so as to expose a part of the valvedisc in the vicinity of the connecting port at the time when the duct isnot connected to the connecting port.

(7) The connector according to any one of the above-described items (1)to (6), in which the valve disc has a pressed section in which a slitsection that is opened due to reception of the pressure from the duct isformed.

(8) In the connector according to the above-described item (7), in whichthe pressed section has a curved convex surface on at least one of asurface on a side with which a distal end surface of the duct contactsand a surface on its back side.

(9) The connector according to the above-described item (7), in whichthe pressed section has a curved concave surface on a surface of a sidewith which a distal end surface of the duct contacts.

(10) The connector according to any one of the above-described items (7)to (9), in which the surface on the back side on the side, with whichthe distal end surface of the duct contacts, of the pressed section isflat.

(11) The connector according to the above-described item (9), in whichthe pressed section has a curved convex surface on the surface on theback side on the side with which the distal end surface of the ductcontacts.

(12) The connector according to the above-described item (7) or (8), inwhich the pressed section has a flat surface on the side with which thedistal end surface of the duct contacts.

(13) The connector according to any one of the above-described items (1)to (6), in which the valve disc has a pressed section provided with aslit section opened upon the natural state and the shape of the valvedisc is regulated by the connecting member upon the non-connectionbetween the duct and the connector main body so that the slit section isclosed.

(14) The connector according to the above-described item (13), in whicha contour in plan view of the pressed section has a non-circular shapeupon the natural state, and the shape of the valve disc is regulated bymeans of the connecting member to become substantially circular.

(15) The connector according to the above-described item (7), in whichthe pressed section has a first convex section on the side with whichthe distal end surface contacts.

(16) The connector according to the above-described item (15), in whichthe first convex section is formed into a substantially dome shape.

(17) The connector according to the above-described item (15) or (16),in which the pressed section has a second convex section projectingopposite the first convex section on the back side of the first convexsection.

(18) The connector according to the above-described item (17), in whichthe second convex section is formed into a substantially hemisphericalshape.

(19) The connector according to any one of the above-described items (1)to (18), in which the fluid passage distance of the connector main bodydefined between the contact surface between the duct and the valve discdisposed at one end of the connector main body and an opening on theother end does not substantially vary with the opening/closing of thevalve disc before and after the connection between the duct and theconnector main body.

(20) The connector according to any one of the above-described items (1)to (19), in which the volume of the fluid passage of the connector mainbody does not substantially vary before and after the connection betweenthe duct and the connector main body.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view in accordance with a first embodiment of aconnector of the present invention, which shows a state that a duct isnot connected.

FIG. 2 is a perspective view in accordance with the first embodiment ofthe connector of the present invention, which shows a state that theduct is connected.

FIG. 3 is a sectional view showing a structural example of a valve discaccording to the present invention.

FIG. 4 is a local sectional view of a side surface in accordance with asecond embodiment of a connector of the present invention, which shows astate that a duct is not connected.

FIG. 5 is a local sectional view of a side surface in accordance withthe second embodiment of the connector of the present invention, whichshows a state that the duct is connected.

FIG. 6 is a local sectional view of a side surface in accordance with athird embodiment of a connector of the present invention, which shows astate that a duct is not connected.

FIG. 7 is a local sectional view of a side surface in accordance withthe third embodiment of the connector of the present invention, whichshows a state that the duct is connected.

FIG. 8 is a local sectional view of a side surface in accordance with afourth embodiment of a connector of the present invention, which shows astate that a duct is not connected.

FIG. 9 is a local sectional view of a side surface in accordance withthe fourth embodiment of the connector of the present invention, whichshows a state that the duct is connected.

FIGS. 10A and 10B are a plan view and a local sectional view of a sidesurface showing an structural example of a valve disc according to thepresent invention.

FIGS. 11A and 11B show the valve disc shown in FIG. 10 and are a planview and a local sectional view of a side surface when the valve disc isturned about its axis by 90 degrees.

FIG. 12 is a local sectional view of a side surface of the valve discshown in FIG. 10, which shows a state that a duct is connected.

FIGS. 13A and 13B are a plan view and a local sectional view of a sidesurface showing an structural example of a valve disc according to thepresent invention.

FIG. 14 is a local sectional view of a side surface of the valve discshown in FIG. 13, which shows a state that a duct is connected.

FIGS. 15A and 15B are a plan view and a local sectional view of a sidesurface showing an structural example of a valve disc according to thepresent invention.

FIGS. 16A and 16B are a plan view and a local sectional view of a sidesurface of the valve disc shown in FIG. 15, which shows a state that theshape of the valve disc is limited by a connecting member.

FIG. 17 is a side sectional view in accordance with a fifth embodimentof a connector of the present invention, which shows a state that a ductis not connected.

FIG. 18 is a side sectional view in accordance with the fifth embodimentof the connector of the present invention, which shows a state that theduct is connected.

FIG. 19 is a side sectional view in accordance with a sixth embodimentof a connector of the present invention, which shows a state that a ductis not connected.

FIG. 20 is a side sectional view in accordance with the sixth embodimentof the connector of the present invention, which shows a state that theduct is connected.

FIG. 21 is a side sectional view showing another example in which aplurality of connectors according to the present invention are provided.

BEST MODE FOR EMBODYING THE INVENTION

A connector according to the present invention will now be described indetail on the basis of preferred embodiments with reference to theaccompanying drawings. The modes of the present invention are notlimited to the embodiments shown.

A first mode of the connector according to the present invention isshown in FIGS. 1 to 3. The connector 1 according to the presentinvention is provided with: a substantially cylindrical connector mainbody 1 having a fluid passage (hereinafter referred to as a flow path)21 in its interior and opened at both ends (241 and 221); a valve disc 5disposed at the opening end 221 that is one of the openings of theconnector main body 2 and made of elastic material for opening the flowpath 21 within the connector main body 2 upon the connection with a duct6 to be connected to the connector main body 2 and closing upon thenon-connection; and a substantially cylindrical duct connecting member 3disposed on the outer periphery of the connector main body 2 on the sideof the valve disc 5 and coaxially with the connector main body 2 to bemovable in an axial direction of the connector main body 2.

An inner diameter (diameter of the flow path 21) of the connector mainbody 2 according to the present invention is usually substantially equalto an outer diameter of a tip end section of the duct 6 to be connectedand never greater than the outer diameter. Accordingly, the duct 6 to beconnected is no longer substantially inserted into the flow path 21through the valve disc 5.

Incidentally, for the sake of the explanation, the explanation will begiven by regarding the side of the valve disc 5 (for example, the leftside on the paper surface of FIGS. 1 and 2 and FIGS. 4 to 9) as a“proximal end” and the opening side (right side on the paper surface) asa “distal end” with respect to a longitudinal direction (horizontaldirection on the paper surface) of the cylindrical connector main body1. The other drawings are based on this rule.

The connector according to the first mode will now be described in moredetail.

FIG. 1 is a perspective view showing a state that the duct 6 is notconnected to the connector 1. FIG. 2 is a sectional perspective viewshowing a state that the duct 6 is connected thereto.

The connector 1 connects the duct 6 and has the substantiallycylindrical connector main body 2, the substantially cylindricalconnecting member 3, a connecting section 4 whereby the connector mainbody 2 and the connecting member 3 are connected with each other and thevalve disc 5 formed of elastic material (flexible material).

As shown in FIGS. 1 and 2, the connector main body 2 has the flow path21 in its interior, and the valve disc 5 is disposed at the end of theopening 221 on the side of a proximal end section 22 of the flow path21.

A ring-shape retainer section 23 that may be brought into contact with astepped section 33 of the connecting member 3 to be described later isprovided on an outer peripheral surface of the proximal end section 22of the connector main body 2, and a taper surface 231 that has an outerdiameter decreasing gradually from the distal end to the proximal end isformed on the proximal end side of the retainer section 23. Upon thenon-connection of the duct 6, the taper surface 231 and a taper surface331 of the stepped section 33 are engaged with each other so that theconnecting member 3 is regulated in position and retained at apredetermined position relative to the connector main body 2.

A taper surface that has an outer diameter decreasing gradually from theproximal end to the distal end is formed on an outer peripheral surfaceof the distal end section 24 of the connector main body 2; that is, theouter peripheral side of the distal end section 24 is formed into a luretaper-shape.

The side of the distal end section 24 of the connector main body 2 isformed into a double sleeve shape and has a substantially cylindrical(outer sleeve) lure lock section 25 having a greater diameter than thatof the distal end section 24. A spiral rib (lure lock screw) 251 isformed in an inner peripheral surface of the lure lock section 25.

A tube (not shown) having, for example, flexibility and the like areconnected liquid-tightly through a predetermined jig or directly on thedistal end side of this connector main body 2 whereby the flow path 21of the connector main body 2 and the inner hole (not shown) of the tubeare in communication with each other. A tube of an infusion set, forexample, is given as this tube. The distal end section 24 of theconnector main body 2 may be inserted into and connected to the tube.Also, the distal end section 24 of the connector main body 2 may be fitto the tube and at the same time, a flange or a lure lock screw (neithershown) on the tube side may be threadedly engaged and locked by the rib251 of the lure lock section 25.

Incidentally, according to the present invention, the lure lock section25 may be dispensed with. Also, the outer diameter of the distal endsection 24 of the connector main body 2 may be kept constant in theaxial direction (longitudinal direction).

The connector 1 has the connecting member 3 disposed on the outer sideof the connector main body 2 and movable in the axial direction of theconnector main body 2.

The connecting member 3 is composed of a proximal end section 31 that isa connecting port section (connecting section) for the duct 6 and adistal end section 32 having a greater diameter than that of theproximal end section 31. Normally, the duct 6 to be inserted into theconnecting member has an outer diameter decreasing gradually toward thedistal end. The proximal end section 31 has an inner diameter that mayallow the insertion length of the duct 6 in which the distal end of theduct 6 pushes and opens the valve disc 5 of the connector main body 2and maintain the duct 6 stably. Also, the inner diameter of thisproximal end section 31 is smaller than the inner diameter of the distalend section 32, somewhat greater than the outer diameter of the distalend section 24 of the connector main body 2 and smaller than the outerdiameter of the retainer section 23 of the connector main body 2. Theinner diameter of the distal end section 32 is somewhat greater than theouter diameter of the retainer section 23 of the connector main body 2.

The stepped section 33 is formed at a boundary (boundary section) of theproximal end section 31 and the distal end section 32. The taper surface331 that has an inner diameter decreasing from the distal end to theproximal end is formed on the inner peripheral side of this steppedsection 33.

A position regulating means for regulating the position of theconnecting member 3 is defined by this stepped section 33 and theretainer section 23 of the above-described connector main body 2.

Also, a ring-shape flange 34 is formed on the proximal end of theconnecting member 3. This flange 34 is threadedly engaged with the lurelock screw (not shown) on the duct 6 side so that the duct 6 is lockedrelative to the connecting member 3. Alternatively, instead of theflange 34 shown, it is possible to form a spiral rib (lure lock screw)to threadedly engage with the lure lock screw (not shown) on the duct 6side on the outer peripheral surface of the proximal end section 31 ofthe connecting member 3.

Also, according to the present invention, the flange 34 of theconnecting member 3 or the rib may be dispensed with.

The connecting member 3 is connected with the connector main body 2 by aconnecting section 4.

The connecting section 4 is constituted of a spiral spring (biasingmeans) 41 and a ring-shape attaching section 42 formed at a tip end ofthis spring 41.

The proximal end of the spring 41 is bonded to a tip end of theabove-described connecting member 3, and the attaching section 42 isbounded to a proximal end of the lure lock section 25 of the connectormain body 2.

As a joint method, fitting (particularly fitting or threadedlyengagement with caulking), adhesion with adhesives and so on areexemplified. Also, in the case where the members connected with eachother are made of resin, it is possible to adopt melt-bonding such asmelt-bonding by heat or melt-bonding by ultrasonic wave.

Here, it is preferable to integrally form the connector main body 2and/or connecting member 3 with the connecting section 4. In particular,it is preferable to integrally form the connecting member 3 with theconnecting section 4. Thus, it is possible to decrease the number ofparts and also to reduce labor upon the assembling work and timerequired for assembly.

The spring 41 is set up so as to be extended to some extent from thenon-loaded state (natural length) upon the connection between the duct 6and the connector 1 and biases the connecting member 3 toward the tipend side (in a direction close to the connector main body 2) relative tothe connector main body 2, i.e., toward the side of the connector mainbody 2 by its restoring force (elastic force).

The valve disc 5 is fixed liquid-tightly (airtightly) to the proximalend opening 221 of the connector main body 2 so as to close the flowpath 21.

In FIG. 2, the distal end of a base body section 55 of the valve disc 5is bonded to the opening 221 end section of the connector main body 2.As a joint method for connecting the valve disc 5 and the connector mainbody 2, the fitting (particularly fitting or threadedly engagement withcaulking), adhesion with adhesives and so on are exemplified. Also, inthe case where the connector main body 2 is made of resin, it ispossible to adopt the melt-bonding such as melt-bonding by heat ormelt-bonding by ultrasonic wave.

A structural example of the valve disc is shown in section in FIG. 3.The valve disc 5 is composed of the substantially cylindrical base bodysection 55 and a pressed section 51 provided to shield the inner hole ofthe base body section 55 on one end side (proximal end side) in theaxial direction of the base body section 55. It is preferable tointegrally form the base body section 55 and the pressed section 51.

The pressed section 51 is a section that receives the pressure from thedistal end surface 62 of the duct 6 and its central section is formedinto a thick section thicker than the outer periphery.

This pressed section 51 has a first convex section 52 with which adistal end surface 62 of the duct 6 is brought into contact. This firstconvex section 52 is formed into a substantially dome-shape (conical,bevel, plate-like or the like) and projects by a predetermined amount(is exposed to the connecting port) from the proximal end opening 311 ofthe connecting member 3 to the outside when the duct 6 is not connectedto the connector 1 (joint port).

Also, the pressed section 51 has a second convex section 53 on the backside of the first convex section 52. This second convex section 53 isformed into a substantially hemispherical shape and projects oppositethe first convex section 52.

Thus, the pressed section 51 preferably has a curved convex surface onat least one of the surface (surface on the proximal end side) on theside with which the distal end surface 62 of the duct 6 is brought intocontact and the surface (surface on the distal end side) on its backside, and more preferably has curved convex surfaces on the surface onthe side with which the distal end surface 62 of the duct 6 is broughtinto contact and the surface on the back side, respectively. Thus, theliquid-tightness (airtightness) may be further enhanced.

A slit section 54 passing through the pressed section 51 is formed inthe central section (thick section) of such a pressed section 51. Inthis embodiment, the slit section 54 is comprised of a straight-line cut(slit) formed to pass through the apexes of the first convex section 52and the second convex section 53.

This slit section 54 is closed by the elasticity of the pressed section51 to hold the liquid-tight state (airtight state) in the non-loadedstate (the state that the external force is not applied).

Incidentally, according to the present invention, the shape of the slitof the slit section 54 is not limited to that shown in the drawings butmay be a cross shape, for example.

Also, according to the present invention, the surface (surface on thedistal end side) on the back side to the side, with which the distal endsurface 62 of the duct 6 is brought into contact, of the pressed section51 may be flat (see FIG. 13B).

Also, according to the present invention, the shape of the pressedsection 51 is not limited to that shown or described above. For example,it is possible to obtain the sufficiently high liquid-tightness(airtightness) even without using the shape of the pressed section 51shown according to a kind of fluid flowing through the flow path 21 ofthe connector 1, a magnitude of the pressure (inner pressure of the flowpath 21) from the flow path 21 side of the connector main body 2, andthe like. In this case, for example, a relatively small rib is providedto the pressed section 51 or a thickness of the pressed section 51(section where the slit section 54 is formed) is set up (adjusted) to asuitable value.

Also, according to the present invention, for example, in the case wherethe duct 6 is not connected to the connector 1 (connecting port), it ispossible to take a structure in which a position in the axial directionof the apex section of the first convex section 52 and a position in theaxial direction of the proximal end of the connecting member 3 aresubstantially identified with each other.

Examples of the structural materials of the connector main body 2, theconnecting member 3, and the connecting section 4 include: polyolefinessuch as a polyethylene, a polypropylene, an ethylene-propylenecopolymer, and an ethylene-vinyl acetate copolymer (EVA); a polyvinylchloride, a polyvinylidene chloride, a polystyrene, a polyamide, apolyimide, a polyamide imide, a polycarbonate, apoly(4-methylpentene-1), an ionomer, an acrylic resin, a polymethylmethacrylate, an acrylonitrile-butadiene-styrene copolymer (ABS resin),an acrylonitrile-styrene copolymer (AS resin), a butadiene-styrenecopolymer; polyesters such as a polyethylene terephthalate (PET), apolybuthylene terephthalate (PBT), and polycyclohexane terephthalate(PCT); a polyether, a polyetherketone (PEK), a polyetheretherketone(PEEK), a polyetherimide, a polyacetal (POM), a polyphenylene oxide, amodified polyphenylene oxide, a polysulfone, a polyethersulfone, apolyphenylene sulfide, a polyarylate, an aromatic polyester (liquidcrystal polymer), polytetrafluoroethylene, polyvinylidene fluoride;various resin materials such as other fluorine resins; and a blendproduct and a polymer alloy containing at least one of theabove-mentioned materials. Further, various glass materials, ceramicmaterials, and metal materials may also be used.

In the case where the connector main body 2, the connecting member 3 andthe connecting section 4 are made of resin, respectively, it is possibleto form them into a desired shape with ease by means of, for example,injection molding.

Moreover, the valve disc 5 consists of an elastic material (flexiblematerial) which is elastic deformable. Examples of the material include:various rubber materials such as natural rubber, isoprene rubber,butadiene rubber, styrene-butadiene rubber, nitrile rubber, chloroprenerubber, butyl rubber, acrylic rubber, ethylene-propylene rubber, hydrinrubber, urethane rubber, silicone rubber, and fluorine rubber; variousthermoplastic elastomers such as styrene-based, polyolefin-based,polyvinyl chloride-based, polyurethane-based, polyester-based,polyamide-based, polybutadiene-based, trans-polyisoprene-based, fluorinerubber-based, and chlorinated polyethylene-based thermoplasticelastomers. Those materials may be used alone or in combination of atleast two of the above-mentioned materials.

The duct 6 is a section or an equipment to be connected to theconnecting port (proximal end section 31 of the connecting member 3) ofthe connector 1. As the duct 6, there is exemplified a tubular equipmentsuch as a tip end projecting section (section to which a needle tube isconnected) of a syringe (injection syringe) or a hub or sheath that isindependent by itself.

The duct 6 has a flow path 61 in its interior. Then, a taper surfacethat has an outer diameter decreasing from the proximal end to thedistal end is formed on the outer peripheral side of the duct 6. Thatis, the outer peripheral side of the duct 6 is formed into a lure tapershape.

The outer diameter of a tip end 63 of the duct 6 is somewhat smallerthan the inner diameter (connecting diameter) of the proximal endsection 31 of the connecting member 3, and the outer diameter of theproximal end of the duct 6 is greater than the inner diameter of theproximal end section 31. Thus, it is possible to insert the tip endsection of the duct 6 into the connecting member 3 from the opening 311and to insert (fit) it into the proximal end section 31 at a desireddepth.

As the structural material for the duct 6, there can be used the samematerial as that for the structural material of the connector main body2, the connecting member 3 and the connecting section 4.

The operation of the connector 1 will now be described.

As shown in FIG. 1, when the duct 6 is not connected to the connector 1(connecting port) (upon non-connected state), the connecting member 3 isbiased toward the tip end side relative to the connector main body 2,i.e., toward the connector main body 2 by the restoring force (elasticforce) of the spring 41, and the stepped section 33 of the connectingmember 3 is retained by the retainer section 23 of the connector mainbody 2 whereby the position of the valve disc 5 is regulated (retained)such that the first convex section 52 project to the outside from theproximal end of the connecting member 3 by a predetermined amount.

Thus, since the first convex section 52 of the valve disc 5 projects tothe connecting port upon the non-connected state, it is possible to, forexample, clean or wipe the surface of the first convex section 52 of thevalve disc 5 to thereby make it possible to keep clean the surface ofthe first convex section 52.

Also, the slit section 54 of the valve disc 5 is biased such that theslit section 54 is closed by the elastic force of the pressed section 51upon the non-connected state, i.e., the non-loaded state (state that theexternal force is not applied) to thereby keep the closed state and tokeep the liquid-tightness (airtightness).

In this case, since the pressure (inner pressure of the flow path 21)from the flow path 21 side of the connector main body 2 is applied so asto close the slit section 54 in the same manner as the elastic force ofthe pressed section 51, it is possible to positively prevent the leakageof the fluid (liquid, gas or the like) from the slit section 54.

As shown in FIG. 1, when the duct 6 is connected to the connector 1(connecting port), the positioning is carried out such that the axis ofthe duct 6 and the axis of the connector 1 (opening 311) coincide witheach other.

Then, the duct 6 in this state is moved to the distal end side (in adirection indicated by the arrow in FIG. 1), and is inserted into theconnector 1 (connecting member 3) from the opening 311 of the connectingmember 3. At this time, the connecting member 3 is moved in a directionaway from the connector main body 2 (proximal end side) against theelastic force of the spring 41.

Thus, as shown in FIG. 2, the spring 41 is elongated, and the pressedsection 51 (first convex section 52) of the valve body 5 is pressed bythe distal end surface 62 of the duct 6. The first convex section 52undergoes elastic deformation, a dome shape thereof is gradually changedto a flat shape, and the first convex section 52 is warped (the surfaceof the pressed section 51 becomes a concave shape).

Along with the change in the shape of the pressed section 51, the slitsection 54 that has been closed gradually opens from the second convexsection 53 side, and finally opens at a predetermined opening. Thus, theflow path 61 of the duct 6 is made to communicate with the flow path 21of the connector main body 2 (flow path of the connector).

As described above, the duct 6 is connected to the connector 1.

As shown in FIG. 2, when the duct 6 is connected to the connector 1(connected state), the distal end surface 62 of the duct 6 is broughtinto airtight (liquid-tight) contact with the valve disc 5. In thiscase, the spring 41 is elongated more than that in the case of thenon-connected state, the valve disc 5 is pressed against the duct 6 byits restoring force whereby the sealability (liquid-tightness,airtightness) between the duct 6 and the valve disc 5 is considerablyenhanced to thereby make it possible to positively prevent the liquidleakage or the like.

Also, under the connected state, the duct 6 is fit to the proximal endsection 31 at a position where its outer diameter coincides with theinner diameter (diameter of the opening 311) of the proximal end section31 of the connecting member 3 that is the connecting port. Thus, it ispossible to prevent the duct 6 from being easily removed away from theconnector 1.

Also, in the connector 1, when the duct 6 is connected to the connector1, the connecting member 3 moves in a direction away from the connectormain body 2. Thus, since it is possible to open the valve disc 5 andmake the flow path 61 of the duct 6 communicate with the flow path 21 ofthe connector main body 2 without invasion of the distal end surface 62of the duct 6 or the outer peripheral surface of the tip end sectioninto the flow path 21 of the connector main body 2 exceeding the valvedisc 5 (without insertion of the duct 6 into the valve disc 5), thevolume (flow path volume) of the flow path 21 of the connector main body2 does not substantially vary before and after the connection of theduct 6 (upon the non-connected state and the connected state). Namely,the volume of the flow path 21 does not substantially vary in accordancewith the opening/closing of the valve disc 5. Also, the distance L froma tip end 63 of the duct 6 to the fluid passage opening 241 (tip end ofthe flow path 21) does not substantially vary before and after theconnection (non-connected state and connected state) of the duct 6 underthe state of contact between the tip end 63 of the duct 6 and the valvedisc 5.

For this reason, in the case where the connector 1 is used to beconnected to the catheter disposed in the blood vessel, for example,since the volume of the flow path 21 of the connector main body 2 doesnot substantially vary even if the duct 6 is removed from the connector1, the blood is no longer sucked into the catheter. Thus, it is possibleto prevent (or suppress) the generation of thrombi within the catheter.

Also, when the duct 6 is connected to the connector 1, since thisconnector 1 does not have the mode in which the distal end surface 62 ofthe duct 6 or the outer peripheral surface of the distal end sectioninvades the flow path 21 of the connector main body 2 exceeding thevalve disc 5 (the duct 6 penetrates through the slit section 54 of thevalve disc 5), the disadvantage that the slit section 54 is excessivelyexpanded to degrade the airtightness (liquid-tightness) is not caused.Also, even if foreign matters (refuse, dust or the like), bacilli or thelike are adhered to the distal end surface 62 of the duct 6 or the outerperipheral surface of the distal end section, it is possible to preventthe foreign matters or the like from entering the flow path 21 of theconnector 2 and contaminating the interior of the flow path 21.

When the duct 6 is removed from the connector 1, the duct 6 in the stateshown in FIG. 2 is moved to the proximal end side and pulled apart fromthe connecting member 3.

Thus, since the pressure applied to the valve disc 5 by the duct 6 isreleased, the valve disc 5 is restored back to the original shapeimmediately by the self-restoring force due to its elasticity andbrought into the above-described state shown in FIG. 1.

As shown in FIG. 1, when the valve disc 5 is returned back to theoriginal shape, the slit section 54 is again closed and restores itsairtightness (liquid-tightness) as mentioned above. Thus, after the duct6 is removed away from the connector 1, even if, for example, the fluidflows in the reverse direction toward the proximal end, it is possibleto prevent the fluid from flowing out (leaking) from the proximal endside of the connector 1.

In particular, in this embodiment, since the slit section 54 is formedin the first convex section 52 and the second convex section 53 that arethe thick sections, it is possible to further enhance the sealabilityupon the closing of the slit section 54 compared with the case where theslit section 54 is formed in the flat section. It is therefore possibleto more positively prevent the liquid leakage against the elevation ofthe inner pressure of the flow path 21 of the connector main body 2, orthe like.

Also, since the connecting member 3 is biased toward the connector mainbody 2 by the restoring force of the spring 41, when the duct 6 isremoved away from the connecting member 3, the connecting member 3 ismoved to the distal end relative to the connector main body 2. In thiscase, since the taper surface 331 is formed on the inner peripheral sideof the stepped section 33 of the connecting member 3, the connectingmember 3 may smoothly move along the taper surface 331.

Then, the stepped section 33 of the connecting member 3 is brought intoabutment with the retainer section 23 of the connector main body 2.Thus, the connecting member 3 is stopped (the connecting member 3 isreturned immediately back to the original position). That is, asdescribed above, the stepped section 33 of the connecting member 3 isretained by means of the retainer section 23 of the connector main body2. Thus, the connecting member 3 is positioned to the connector mainbody 2 (valve disc 5) such that the first convex section 52 of the valvedisc 5 projects from the proximal end of the connecting member 3 to theoutside by a predetermined amount and brought into the above-describedstate shown in FIG. 1.

The above-described effect can be obtained by the connector 1.

Also, the connector does not have a mode in which the duct 6 isconnected so as to pass through the slit section 54 of the valve disc 5as described above. Accordingly, the slit section 54 is not excessivelyexpanded. As a result, even if the removal of the duct 6 to theconnector 1 is repeatedly performed many times, the sealability of thevalve disc 5 in the slit section 54 is hardly degraded.

Also, since the connector 1 does not have a mode in which the valve disc5 is moved within the flow path 21, it is unnecessary to provide a venthole (through-hole) for making the flow path 21 communicate with theoutside. It is thus possible to prevent the contamination of theinterior of the flow path 21 of the connector main body 2.

Also, in the connector 1, since the duct 6 is connected directly andused without using a needle, there arises no problem such as erroneousinjection by a medial worker and its safety aspect is high.

Also, in the connector 1, it is possible to perform theattachment/detachment of the duct with a slight force, which is superiorin operationability.

Also, in the connector 1, the connecting member 3 is adapted to move inthe axial direction to the connector main body 2, so that the number ofparts may be reduced relatively to thereby make it possible to simplifythe structure. Thus, it is possible to reduce the labor in assemblingand to reduce the time required for assembling.

Also, the connector 1 is advantageous of miniaturization. For example,it is possible to apply the connector with ease to the tube in aninfusion set, a chemicals feed inlet or the like.

Other modes of a connector according to the present invention will nowbe described. In the following modes, the same reference numerals areused to indicate the parts that are same as or corresponding to those inFIGS. 1 to 3. The explanation will be omitted for the common pointsindicated by the same reference numerals and only the main differencewill be explained.

A second embodiment of a connector according to the present inventionwill now be described with reference to FIGS. 4 and 5.

FIG. 4 is a local sectional view of a side surface of the connectoraccording to the present invention, which shows the state that the duct6 is not connected to the connector 1 of the second embodiment. FIG. 5is a local sectional view of a side surface, which shows the state thatthe duct 6 is connected to the connector 1.

In the connector 1 shown in these drawings, the outer diameter of aproximal end section 551 of the base body section 55 of the valve disc 5is smaller than the outer diameter of a distal end section 552.

A stepped section 553 that may retain the distal end section 32 of theconnecting member 3 to be described later (that may come into contactwith the distal end section 32) is formed at a boundary (boundarysection) of the proximal end section 551 and the distal end section 552.A taper surface 554 that has an outer diameter decreasing from thedistal end to the proximal end is formed on the outer peripheral side ofthe stepped section 553.

A ring-shape rib 555 is formed at a tip end of the base body section 55.A hole section 556 passing in the axial direction is formed in this rib555.

A stepped section is formed in the distal end section 32 of theconnecting member 3. The taper surface 331 having an inner diameterdecreasing from the distal end to the proximal end is formed on theinner peripheral side of this distal end section 32.

A position regulating means for regulating the position of theconnecting member 3 is defined by this distal end section 32 and thestepped section 553 of the valve disc 5.

The connecting section 4 is constituted of the spiral spring (biasingmeans) 41 and an engagement claw 43 formed at the tip end of this spring41.

The proximal end of the spring 41 is bonded to the tip end of theconnecting member 3.

On the other hand, the tip end section of the spring 41 is inserted intothe hole section 556 of the rib 555 of the valve disc 5, and theengagement claw 43 is engaged with the rib 555 under this state tothereby connect the distal end section of the spring 41 to the rib 555of the valve disc 5.

Namely, the valve disc 5 and the connecting member 3 are connected witheach other by means of this connecting section 4.

Incidentally, as described in conjunction with the connector 1 accordingto the above-described first embodiment, it is preferable to integrallyform the connecting member 3 and the connecting section 4 also in thisconnector 1.

As described above, according to this connector 1, it is possible toobtain the same effect as that of the connector 1 in the above-describedfirst embodiment.

Also, it is possible to easily connect the valve disc 5 and theconnecting member 3 by the connecting section 4 even without usingadhesive technology or the like. Thus, it is possible to assemble theconnector 1 with ease.

A third embodiment of a connector according to the present inventionwill now be described with reference to FIGS. 6 and 7. FIG. 6 is a localsectional view of a side surface, which shows the state that the duct 6is not connected to the connector 1 of the third embodiment. FIG. 7 is alocal sectional view of a side surface, which shows the state that theduct 6 is connected to the connector 1.

In the connector 1 shown in these drawings, the outer diameter of theproximal end section 551 of the base body section 55 of the valve disc 5is smaller than the outer diameter of the distal end section 552.

A stepped section 553 that may engage with the stepped section 33 of theconnecting member 3 (that may come into abutment against the steppedsection 33) is formed at a boundary (boundary section) of this proximalend section 551 and the distal end section 552. A taper surface 554 thathas an outer diameter decreasing from the distal end to the proximal endis formed on the outer peripheral side of this stepped section 553.

A position regulating means for regulating the position of theconnecting member 3 is defined by this stepped section 553 and thestepped section 33 of the connecting member 3.

The connecting section 4 is composed of a bellows-like spring (biasingmeans) 44 and a ring-like attaching section 45 formed at a tip end ofthis spring 44. A ring-like slit 451 passing in the axial direction isformed in this attaching section 45.

The spring 44 is disposed under the state that it somewhat shrinks fromthe non-loaded state (natural length) and biases the connecting member 3toward the tip end side to the connector main body 2 (in a directioncloser to the connector main body 2), i.e., toward the connector mainbody 2 by its restoring force (elastic force).

A ring-like flange 35 is formed at a tip end of the connecting member 3.

The spring 44 is located in the interior (inside) of this connectingmember 3, and the proximal end of the spring 44 is bonded to the tip endof the valve disc 5.

On the other hand, the distal end side of the connecting member 3 isinserted into the slit 451 of the attaching section 45 of the connectingsection 4 and the rib 35 is engaged with the attaching section 45 underthis state whereby the attaching section 45 of the spring 44 and thedistal end side of the connecting member 3 are connected with eachother. Namely, the valve disc 5 and the connecting member 3 areconnected with each other by means of the connecting section 4.

Incidentally, as described in conjunction with the connector 1 accordingto the above-described first embodiment, also in this connector 1, it ispreferable to integrally form the valve disc 5 and the connectingsection 4.

When the duct 6 is connected to the connector 1 (connecting port), asshown in FIG. 7, the connecting member 3 is moved in a direction awayfrom the connector main body 2 (toward the proximal end side) so thatthe spring 44 shrinks.

As described above, according to this connector 1, it is possible toobtain the same effect as that of the connector 1 of the above-describedfirst embodiment.

Also, in this connector 1, since the spring 44 of the connecting section4 is located in the interior (inside) of the connecting member 3, thereis no fear that anything is brought into direct contact with the spring44.

It is thus possible to perform the connecting work safely even if theduct 6 having no lock mechanism is to be connected to the connector 1.

Also, since the spring 44 of the connecting section 4 is located in theinterior of the connecting member 3, it is possible to take any shapefor the outer peripheral shape of the connecting member 3. For instance,it is possible to provide a curved surface or a rib (knurl) or the likecorresponding to fingers on the outer peripheral side of the connectingmember 3 and to perform with ease a device such as facilitating to gripthe connector 1. Also, in this connector 1, it is possible to connectthe valve disc 5 and the connecting member 3 with each other with easeby means of the connecting section 4 without using adhesive technologyor the like, thereby making it possible to assemble the connector 1 withease.

A fourth embodiment of a connector according to the present inventionwill now be described with reference to FIGS. 8 and 9.

FIG. 8 is a local sectional view of a side surface, which shows thestate that the duct 6 is not connected to the connector 1 of the fourthembodiment. FIG. 9 is a local sectional view of a side surface, whichshows the state that the duct 6 is connected to the connector 1.Incidentally, the explanation will be omitted for the common points ofthe connector 1 of the above-described first embodiment and only themain differences will be explained.

In the connector 1 shown in these drawings, the inner diameter of theproximal end section 551 of the base body section 55 of the valve disc 5is smaller than the inner diameter of the distal end section 552.

The connecting section 4 is composed of a step-like spring (biasingmeans) 46 and a ring-like attaching section 45 formed at a tip end ofthis spring 46. A ring-like slit 451 passing in the axial direction isformed in this attaching section 45.

The spring 46 is disposed under the state (shrunk state) that a movablesection 461 somewhat bends from the non-loaded state and biases theconnecting member 3 toward the tip end side to the connector main body 2(in a direction close to the connector main body 2), i.e., toward theconnector main body 2 by its restoring force (elastic force).

A position regulating means for regulating the position of theconnecting member 3 is defined by this movable section 461 of the spring46 and the stepped section 33 of the connecting member 3.

The ring-like flange 35 is formed at the tip end of the connectingmember 3.

The spring 46 is located in the interior (inside) of this connectingmember 3, and the proximal end of the spring 46 is bonded to a middlepart of the proximal end section 551 of the valve disc 5.

On the other hand, the distal end side of the connecting member 3 isinserted into the slit 451 of the attaching section 45 of the connectingsection 4 and the flange 35 is engaged with the attaching section 45under this state whereby the attaching section 45 of the spring 46 andthe distal end side of the connecting member 3 are connected with eachother.

Namely, the valve disc 5 and the connecting member 3 are connected witheach other by means of the connecting section 4.

Incidentally, as described in conjunction with the connector 1 accordingto the above-described first embodiment, also in this connector 1, it ispreferable to integrally form the valve disc 5 and the connectingsection 4.

When the duct 6 is connected to the connector 1 (connecting port), asshown in FIG. 9, the connecting member 3 is moved in a direction awayfrom the connector main body 2 (toward the proximal end side) so thatthe movable section 641 of the spring 46 bends toward the connector mainbody 2 side.

The spring 46 has the stronger restoring force (restoring force toreturn the movable section 461 back to the original position) to returnto the original state in the initial moving period (state shown in FIG.8) than in the final moving period (state shown in FIG. 9).

For this reason, in this connector 1, when the duct 6 is connected tothe connector 1 (upon the connected state), the restoring force of thespring 46 is weak in comparison with the case upon the non-connectedstate. This feeling is felt by the hand so that it is possible topositively grip with ease the fact that the duct 6 has been connected tothe connector 1.

Also, in this connector 1, in comparison with the case of using thebiasing means, such as a spiral spring, whose restoring force isincreased as it is shrunk and whose restoring force is increased as itis elongated, since it is possible to weaken the restoring force of thespring 46 under the connected state, it is possible to hold theconnected state positively by engaging the duct 6 with the proximal endsection 31 of the connecting member 3 even if the duct 6 having no lockmechanism is connected to the connector 1.

As described above, according to this connector 1, it is possible toobtain the same effect as that of the connector 1 according to theabove-described first embodiment.

Also, in this connector 1, since the spring 46 of the connecting section4 is located in the interior (inside) of the connecting member 3, thereis no fear that anything is brought into direct contact with the spring46.

It is thus possible to perform the connecting work safely even if theduct 6 having no lock mechanism is to be connected to the connector 1.

Also, since the spring 46 of the connecting section 4 is located in theinterior of the connecting member 3, it is possible to take any shapefor the outer peripheral shape of the connecting member 3. For instance,it is possible to provide a curved surface or a rib (knurl) or the likecorresponding to fingers on the outer peripheral side of the connectingmember 3 and to perform with ease a device such as facilitating to gripthe connector 1.

Also, in this connector 1, it is possible to connect the valve disc 5and the connecting member 3 with each other with ease by means of theconnecting section 4 without using adhesive technology or the like,thereby making it possible to assemble the connector 1 with ease.

As described above, the connector according to the present invention hasbeen described on the basis of the embodiments. However, the presentinvention is not limited to these. It is possible to replace eachstructure to any desired structure having the same function.

For example, according to the present invention, it is possible tocombine the above-described embodiments suitably.

Also, according to the present invention, the valve disc 5 is notlimited to each of the embodiments. Other structural examples of thevalve disc 5 will now be described. Incidentally, for the sake of theexplanation, the explanation will be given while regarding theup-and-down direction as an “axial direction”, the upper side as a“proximal end” and the lower side as a “distal end” on the paper surfaceof each sectional view of the valve disc. Also, the common point withthe valve disc 5 of the connector 1 according to each embodimentdescribed above will be omitted and only the main differences will bedescribed.

FIG. 10 corresponds to a plan view showing a structural example of thevalve disc 5 (FIG. 10A) and a local sectional view of a side surface(FIG. 10B). FIG. 11 shows the valve disc 5 shown in FIG. 10 andcorresponds to a plan view (FIG. 11A) and a local sectional view of aside surface (FIG. 11B) when the valve disc 5 is rotated about itscenter axis by 90 degrees and FIG. 12 shows the valve disc 5 shown inFIG. 10 and is a local sectional view of a side surface, which shows thestate that the duct 6 is connected thereto.

As shown in FIGS. 10 and 11, the pressed section 51 of this valve disc 5has a curved concave surface 56 on a surface (surface on the proximalend side) on the side with which the distal end surface 62 of the duct 6is brought into contact and a curved convex surface 57 on a surface(surface on the distal end side) on its back side.

In the plan views shown in FIGS. 10A and 11A, the curved concave surface56 is curved in a direction perpendicular to the slit section 54 and isnot curved in the direction in parallel with the slit section 54.

Namely, the shape of the curved concave surface 56 has a shape such asan inner cylindrical peripheral surface with the axis (center axis) inthe up-and-down direction in the plan view shown in FIG. 10A. A pair oflinear apex sections 561 and 562 of this curved concave surface 56 arearranged on both sides through the slit section 54 and in parallel withthe slit section 54 in the plan view shown in FIGS. 10A and 11A.

Also, the shape of the curved convex surface 57 forms a substantiallyspherical surface (shape like a hemispherical surface).

As shown in FIG. 12, when the duct 6 is connected to the connector 1,the pressed section 51 of the valve disc 5 is pressed by means of thedistal end surface 62 of the duct 6, the slit section 54 is opened at apredetermined opening degree so that the flow path 61 of the duct 6 andthe flow path 21 of the connector main body 2 are in communication witheach other through this valve disc 5.

In this valve disc 5, since the curved concave surface 56 is formed onthe proximal end side of the pressed section 51 as described above, theslit section 54 is likely to be opened when the pressed section 51 ispressed by means of the duct 6. Namely, the slit section 54 is openedlargely.

Incidentally, the shape of the curved convex surface 57 may be the shapesuch as a cylindrical peripheral surface, for example.

FIG. 13 corresponds to a plan view (FIG. 13A) showing a structuralexample of the valve disc 5 and a local sectional view (FIG. 13B)showing its side surface. FIG. 14 shows the valve disc 5 shown in FIG.13 and is a local sectional view of a side surface, which shows thestate that the duct 6 is connected.

As shown in FIG. 13B, the pressed section 51 of this valve disc 5 hasthe curved concave surface 56 on a surface (surface on the proximal endside) on the side with which the distal end surface 62 of the duct 6 isbrought into contact and a surface (surface on the distal end side) onits back side is flat (flat surface 58).

In the plan view shown in FIG. 13A, the curved concave surface 56 iscurved in a direction perpendicular to the slit section 54 and is notcurved in the direction in parallel with the slit section 54.

Namely, the shape of the curved concave surface 56 has a shape such asan inner cylindrical peripheral surface with the axis (center axis) inthe up-and-down direction in the plan view shown in FIG. 13A. The pairof linear apex sections 561 and 562 of this curved concave surface 56are arranged on both sides through the slit section 54 and in parallelwith the slit section 54 in the plan view shown in FIG. 13A.

As shown in FIG. 14, when the duct 6 is connected to the connector 1,the pressed section 51 of the valve disc 5 is pressed by means of thedistal end surface 62 of the duct 6, the slit section 54 is opened at apredetermined opening degree so that the flow path 61 of the duct 6 andthe flow path 21 of the connector main body 2 are in communication witheach other through this valve disc 5.

FIG. 15 is a plan view (A) and a local sectional view (FIG. 15B) of aside surface, which shows still another structural example of the valvedisc 5. FIG. 16 shows the valve disc 5 shown in FIG. 15 and a plan view(A) and a sectional view (FIG. 16B) of a side surface, which shows thestate that the shape of the valve disc 5 is regulated by the connectingmember 3.

As shown in FIG. 15, the slit section 54 opened under the natural stateis formed in the central section of the pressed section 51 of this valvedisc 5. This slit section 54 passes through the pressed section 51.

Here the above-described “natural state” means the non-loaded state inwhich the external force is not applied to the valve disc 5.

Also, a contour (contour shape) in a plan view of the pressed section51, i.e., a contour of the pressed section 51 when the pressed section51 is projected onto the plan view perpendicular to the axial directionforms an oblong shape (non-circular shape) under the natural state.

Also, the surface (surface on the proximal end side) of the side withwhich the distal end surface 62 of the duct 6 contacts and the surface(surface on the distal end side) on the back side thereof of the pressedsection 51 are each flat (flat surfaces 59 and 58).

When the connector 1 provided with this valve disc 5 is assembled (thevalve disc 5 is mounted on the connector 1) and the duct 6 is notconnected to the connector 1 (upon the non-connected state), the valvedisc 5 is located at the proximal end section 31 of the connectingmember 3 (see FIG. 1) and the shape of the valve disc 5 is regulated bythis proximal end section 31.

Thus, as shown in FIG. 16, the contour of the plan view of the pressedsection 51 is formed into a substantially circular shape (the same shapeas the inner shape of the proximal end section 31) and the slit section54 is closed.

Then, when the duct 6 is connected to the connector 1, the valve disc 5is located at the distal end section 32 of the connecting member 3 (seeFIG. 2). Namely, the regulation of the shape of the valve disc 5 by theproximal end section 31 is released.

Thus, as shown in FIG. 15, the contour in the plan view of the pressedsection 51 is returned back to the original shape, i.e., the oblongshape (non-circular shape), and the slit section 54 is opened so thatthe flow path 61 of the duct 6 and the flow path 21 of the connectormain body 2 are in communication with each other through this valve disc5.

Also, according to the present invention, the valve disc 5 may be formedof elastic material of two different kinds of materials in compositionor characteristics (flexibility, bending elastic rate, rubber hardnessor the like).

Also, in the above-described embodiments, the shape of the slit of theslit section 54 is formed into the straight-line or the cross-shaped.However, according to the present invention, the shape is not limited tothose but may be formed into, for example an L-shape, an H-shape, aU-shape or the like. Furthermore, at the time when the flow rate of thefluid has to be increased or decreased in accordance with the use, andso on, a plurality of slits may be formed in the slit section 54.

A fifth embodiment is shown in FIGS. 17 and 18 as still another mode ofa connector according to the present invention.

FIG. 17 is a side sectional view showing a state that the connector 1and the duct 6 are not connected to each other, and FIG. 18 is a sidesectional view showing the state that the duct 6 is connected to theconnector 1.

According to this mode, the duct 6 has a lure lock 64 provided with aspiral rib (lure lock screw) 251 on an inner periphery on a tip endsection of the duct. The duct distal end surface 62 is projected by apredetermined length from a tip end of a section of the lure lock 25.

Upon the connected state (FIG. 17), the duct 6 is not only connected andfit to the opening 311 of the connecting member 3 but also it is fixedby means of the engagement between the lure lock 64 of the duct 6 andthe connecting member 3 (flange 34) of the connector 1.

The connecting member 3 has the flange 34 and the long taper surface 331in the stepped section 33.

The valve disc 5 has the pair of apexes 561 and 562 having the distalend surface 62 formed into the curved concave surface 56 substantiallyin the same manner as in FIG. 10B in a side sectional view in thevicinity of the pressed section 51 and the curved convex surface 57 onits back surface. The rib 555 is provided at a tip end of the base bodysection 55 of the valve disc 5. Furthermore, a convex retainer section557 is provided on an outer periphery of the base body section 55. Anotch 558 that may be bent upon depression from the distal end sectionis provided on a side wall of the base end side from the retainersection 557.

The slit 54 has a wedge-shaped opening that has the flow path 21 side ofthe connector main body narrowed in diameter by the bending of the notch558 due to the depression from the distal end section.

The connecting section 4 is composed of a spiral spring (biasing means)41 and a cylindrical attaching section 47 arranged around an axial outerperiphery from the distal end of the connector main body 2 to the distalend side in which the lure lock is formed. The number of windings ofthis spring 41 may be higher than that of the spring shown in FIG. 1.The attaching section 47 fixes one end of the spring 41 by a groove 471formed on its distal end side and fixes the rib 555 of the valve disc 5to the connector main body 2 by a retainer 472 formed at the other endon the proximal end side. Thus, the valve disc 5 is positively fixed tothe connector main body 2. Also, since the connecting member 3 is slidthrough a long stroke along the attaching section 47 along a barrelsection of the connector main body 2 upon the connection with the duct6, it is possible to perform the connection smoothly and stably.

Also, the valve disc 5 is held in a predetermined position by theretention of the valve disc 5 to the proximal end side wall by theopening 311 of the connecting member 3 and the retention of the convexretainer section 557 to the taper surface 331 of the connecting member3.

FIGS. 19 and 20 show a sixth embodiment of a connector according to thepresent invention. FIG. 19 is a side sectional view showing a state thatthe connector 1 and the duct 6 are not connected to each other, and FIG.20 is a side sectional view showing the state that the duct 6 isconnected to the connector 1.

In the drawing, the valve disc 5 shows a modified mode of the valve disc5 and the connecting section 4 shown in FIG. 4 and the function of thestepped spring 461 in FIG. 4 is given to the valve disc 5.

The connector main body 2 has a valve insertion barrel section 26 havinga smaller outer diameter on the proximal end side of the proximal endsection 22 and the flow path 21 is somewhat expanded on the proximal endsurface of the barrel section 26. According to this mode, the base bodysection 55 of the valve disc 5 has a shape to cover the proximal endsection 22 including the barrel section 26 of the connector main body 2and a wing 559 that extends in a double tube shape outwardly from thetip end rib 555 of the base body section 55. The tip end section 560 ofthe wing 559 is pressed and fixed to the intermediate vicinity to thebase body section 55 by a proximal end 48 of the connecting section 4and the tip end section 32 of the connecting member 4 (in thenon-connected state).

A part of the base body section outer periphery of the valve disc 5 isfixed to the connector main body 2 by the ring-like retainer 49.

Upon the connection (FIG. 20), when the lure lock 64 of the duct 6 andthe connecting member 3 (flange 34) of the connector 1 are engaged witheach other, and the outer periphery of the duct 6 is fit in the opening311 of the connecting member 3, the wing 559 of the valve disc 5 extendsfrom the vicinity of the ring-like retainer 49 to the proximal end sideto follow the movement of the connecting member 3.

FIG. 21 shows still another mode of a connector according to the presentinvention and an example in which a plurality of connectors 1 arearranged in parallel. FIG. 21 shows an example in which three connectorsare arranged in parallel. Each connector 2 has the same structure withthe same arrangement as that of each of the valve disc 5, the connectingmember 3 and the connecting section 4 shown in FIGS. 19 and 20.

The connecting pipe 7 has a flow path 72 in the interior and has aplurality of openings 73 in the body side wall 72 thereof. According tothe mode shown in FIG. 21, the connector main body 2 is composed bymaking one the tip end opening 241 of each connector main body 2 andeach opening 73 of the connecting pipe 7 to be continuous with the bodyside wall 71 of the connecting pipe 7 and to be formed integrallypreferably.

In such a connecting pipe, it is possible to introduce a plurality ofkinds of liquids by a single catheter by providing a plurality ofconnectors used in, for example, a universal plug, a syringe, aninfusion container, a medicine liquid container, a catheter, a needle orthe like to thereby make it possible to reduce the load to be imposed onthe patient.

INDUSTRIAL APPLICABILITY

As described above, in the connector according to the present invention,since the volume of the flow path does not substantially vary before andafter the connection of the duct, when the duct is detached from andattached to the connector, it is possible to prevent the fluid (liquid,gas or the like) from being accidentally sucked or discharged.

For instance, in the case where the connector is connected to thecatheter disposed in the blood vessel and used, even if the duct isremoved from the connector, there is no fear that the blood is suckedinto the catheter to thereby make it possible to prevent (or suppress)the generation of thrombi within the catheter.

What is claimed is:
 1. A connector comprising: a substantiallycylindrical connector main body having a flow path in its interior andopened at both ends; a valve disc disposed at one of opening ends ofsaid connector main body and made of elastic material for opening saidfluid passage within the connector main body upon the connection with aduct to be connected to the connector main body and closing upon thenon-connection; and a substantially cylindrical connecting memberdisposed on the outer periphery of said connector main body on a side ofsaid valve disc and coaxially with the connector main body to be movablein an axial direction of the connector main body.
 2. A connectoraccording to claim 1, wherein said valve disc is opened by a pressurefrom said duct without said duct passing through the interior of thevalve disc.
 3. A connector according to claim 1, wherein said duct isfit to an opening of said connecting member to thereby connect and holdthe duct.
 4. A connector according to claim 1, further comprisingbiasing means for biasing said connecting member toward said connectormain body.
 5. A connector according to claim 4, wherein said biasingmeans is composed of a spiral spring, a bellows spring or a stepwisespring.
 6. A connector according to claim 1, further comprising positionregulating means for regulating a position of said connecting member soas to expose a part of said valve disc in the vicinity of saidconnecting port at the time when said duct is not connected to saidconnecting port.
 7. A connector according to claim 1, wherein said valvedisc has a pressed section in which a slit section that is opened due toreception of the pressure from said duct is formed.
 8. A connectoraccording to claim 7, wherein said pressed section has a curved convexsurface on at least one of a surface on a side with which a distal endsurface of said duct contacts and a surface on its back side.
 9. Aconnector according to claim 7, wherein said pressed section has acurved concave surface on a surface on a side with which a distal endsurface of said duct contacts.
 10. A connector according to claim 9,wherein said pressed section has a curved convex surface on the surfaceon the back side on the side with which the distal end surface of saidduct contacts.
 11. A connector according to claim 7, wherein the surfaceon the back side on the side, with which the distal end surface of saidduct contacts, of said pressed section is flat.
 12. A connectoraccording to claim 7, wherein said pressed section has a flat surface onthe side with which the distal end surface of said duct contacts.
 13. Aconnector according to claim 7, wherein said pressed section has a firstconvex section on the side with which the distal end surface of saidduct contacts.
 14. A connector according to claim 13, wherein said firstconvex section is formed into a substantially dome shape.
 15. Aconnector according to claim 13, wherein said pressed section has asecond convex section projecting opposite the first convex section onthe back side of said first convex section.
 16. A connector according toclaim 15, wherein said second convex section is formed into asubstantially hemispherical shape.
 17. A connector according to claim 1,wherein said valve disc has a pressed section provided with a slitsection opened upon the natural state and the shape of said valve discis regulated by said connecting member upon the non-connection betweensaid duct and said connector main body so that said slit section isclosed.
 18. A connector according to claim 17, wherein a contour in planview of said pressed section has a non-circular shape upon the naturalstate, and the shape of said valve disc is regulated by means of saidconnecting member to become substantially circular.
 19. A connectoraccording to claim 1, wherein the fluid passage distance of saidconnector main body defined between the contact surface between saidduct and said valve disc disposed at one end of said connector main bodyand an opening on the other end does not substantially vary with theopening/closing of the valve disc before and after the connectionbetween said duct and said connector main body.
 20. A connectoraccording to claim 1, wherein the volume of said fluid passage of saidconnector main body does not substantially vary before and after theconnection between said duct and said connector main body.